1. Field of the Invention
The present invention relates to a glass run adapted to be attached to a door frame of a motor vehicle to provide a seal between a door opening portion and a vehicle door.
2. Description of Related Art
In order to provide a seal between a door opening portion and a vehicle door having a door sash, in one example of conventional seal structures, an opening trim weather strip is attached to a flange provided in the door opening portion, and a door weather strip is attached to an outer periphery of the door sash. When the vehicle door is closed, a tubular seal portion of the opening trim weather strip contacts a protrusion of the door sash, and a tubular seal portion and a seal lip of the door weather strip contact an outer panel of the door opening portion to seal a gap between the door opening portion and the vehicle door.
In this case, an end edge of the door glass is held with a glass run that is attached along an inner periphery of the door sash, and the door glass is raised and lowered in a channel provided in the glass run to have a generally U-shaped cross-section. This glass run effects a seal between the door glass and the door sash.
With this arrangement, the glass run, the door sash, and a center pillar are exposed around the door glass of a vehicle to degrade the external appearance of a side body of the vehicle so that it has been required to improve the design thereof. In addition, the glass run exists between the door sash and the door glass, and between the center pillar and the door glass so that gaps exist in an exterior surface between the door sash and the door glass, whereby the design of the side body is less preferable.
Under the above-described circumstances, as shown in FIG. 1, in a sashless door-type vehicle body, an exterior part of a door sash is removed so that only a door glass 10 is freely raised and lowered above the door belt line of a vehicle door 12. With this arrangement, in the side body of the motor vehicle, only the door glass 10 is visible above the door belt line of the vehicle door 12.
As shown in FIG. 2, a glass run 14 includes a glass run section 16 adapted to provide a seal between the door glass 10 and a door frame 18, and a trim section 20 adapted to attach the glass run 14 to a flange 22 extending along an end edge of the door frame 18 (see Japanese patent application laid-open No. 2005-247294, for example). The glass run section 16 has a main body with a generally U-shaped cross-section, which includes an outer side wall 24, an inner side wall 26 and a bottom wall 28. And an outer seal lip 30 and an inner seal lip 32 respectively extend from ends of the outer side wall 24 and the inner side wall 26 obliquely in an interior space of the main body. The outer seal lip 30 and the inner seal lip 32 provide a seal against the door glass 10.
The trim section 20 has a generally U-shaped cross-section, which includes a side wall 34 formed integrally with the bottom wall 28 of the glass run section 16, a side wall 36 formed on the side of a vehicle body, and a bottom wall 38. Seal lips 40 and 42 extend from the side wall 36 for contacting and sealing a door opening portion 44 when the vehicle door 12 is closed. A metal insert 45 having a generally U-shaped cross-section is embedded in the side walls 34 and 36 along with the bottom wall 38.
The glass run 14 thus arranged is formed linearly by extruding the glass run section 16 and the trim section 20 along with the metal insert 45 simultaneously.
Since the glass run 14 includes the metal insert 45, the weight thereof is great, thereby increasing the entire rigidity of the glass run 14. When the glass run 14 is attached along a curved outer periphery of an upper side of the door frame 18, it has been required to cut the extruded glass run 14 to have a short length, bend it to conform to curved surfaces of the door frame 18 and join it to another one.
And, when the glass run 14 is bent to conform to the curved surfaces of the door frame 18, wrinkles and waviness may occur in the surface of the glass run 14.
FIG. 3 illustrates another example of a conventional glass run. A glass run 46 includes a glass run section 48 adapted to provide a seal between the door glass 10 and the door frame 18, and a trim section 50 adapted to attach the glass run 46 to the flange 22 provided in the door frame 18, similarly to the case of the glass run 14 (FIG. 2). The glass run section 48 has a main body with a generally U-shaped cross-section, which includes an outer side wall 52, an inner side wall 54 and a bottom wall 56. An outer seal lip 58 and an inner seal lip 60, respectively extend from ends of the outer side wall 52 and the inner side wall 54 obliquely in an interior space of the main body. And the outer seal lip 58 and the inner seal lip 60 provide a seal against the door glass 10.
The trim section 50 has a generally U-shaped cross-section, and includes a side wall 62 formed integrally with the bottom wall 56 of the glass run section 48, a side wall 64 formed on the side of a vehicle body, and a bottom wall 66. A seal lip 68 extends from the side wall 64 for contacting and sealing the door opening portion 44 when the vehicle door 12 is closed. Since no metal insert is used, the outer side wall 52, the bottom wall 56, the side walls 62, 64 and the bottom wall 66 are composed of a hard synthetic resin. And in order to improve the appearance, a shining film may be bonded to the outer side wall 52, the side wall 64 and the bottom wall 66 (see Japanese patent application laid-open No. 2010-18130, for example).
In this case, the glass run 46, however, exhibits a great rigidity in portions composed of a hard synthetic resin so that, upon the bending of the glass run 46 along curved surfaces of an upper side of the door frame 18, wrinkles, waviness or other defects may occur in the shining film on greatly curved areas thereof.